Guest passes can be purchased through the Memberment website or on your behalf by an authorized person. 

Website
When you log into Memberment from the web, you'll see a green "Pool and Guest Passes" button. Click it to start buying passes. 

App
A gate attendant, property manager, or board member can scan your access pass and buy guest passes for you. They will need your credit/debit card on file or available to scan.